An apparatus and a method for indirectly cooling a superconducting quantum interference device (SQUID) are provided. The apparatus includes an outer container extending in a vertical direction; a metallic inner container inserted into the outer container to store a liquid coolant, the metal inner container including a top plate; a SQUID sensor module disposed between a bottom surface of the outer container and a bottom surface of the inner container; a heat transfer pillar adapted to cool the SQUID sensor module, the heat transfer pillar having one end connected to the bottom surface of the inner container and the other end directly or indirectly connected to the SQUID sensor module; a magnetic shield part formed of a superconductor covering a top surface of the SQUID sensor module; and a heat conduction plate being in thermal contact with the other end of the heat transfer pillar.

An apparatus and a method for indirectly cooling a superconducting quantum interference device (SQUID) are provided. The apparatus includes an outer container extending in a vertical direction; a metallic inner container inserted into the outer container to store a liquid coolant, the metal inner container including a top plate; a SQUID sensor module disposed between a bottom surface of the outer container and a bottom surface of the inner container; a heat transfer pillar adapted to cool the SQUID sensor module, the heat transfer pillar having one end connected to the bottom surface of the inner container and the other end directly or indirectly connected to the SQUID sensor module; a magnetic shield part formed of a superconductor covering a top surface of the SQUID sensor module; and a heat conduction plate being in thermal contact with the other end of the heat transfer pillar.

Superconducting output amplifiers having return to zero to non-return to zero converters are described. An example superconducting output amplifier (OA) includes a first superconducting OA stage having a first DC-SQUID and a second DC-SQUID arranged in parallel to the first DC-SQUID. The superconducting OA includes an input terminal for receiving a single flux quantum (SFQ) pulse train. The superconducting OA includes a first splitter configured to split a first set of SFQ pulses corresponding to the SFQ pulse train into a first return to zero (RZ) signal and a second RZ signal. The superconducting OA includes a first return to zero to non-return to zero (RZ-NRZ) converter configured to convert the first RZ signal into a first non-return to zero (NRZ) signal for driving the first DC-SQUID, and a second RZ-NRZ converter configured to convert the second RZ signal into a second NRZ signal for driving the second DC-SQUID.

The invention relates to a method for determining the component of a magnetic field in a predetermined direction. The method comprises preparing a quantum system in a coherent superposition state (S1), letting the quantum system evolve for a delay time period (S2) and performing a readout operation and a projective measurement on the quantum system (S3). The steps (S1, S2, S3) are iteratively repeated in an iteration loop, wherein the delay time period increases linearly by the same time increment after each iteration. The method further comprises determining the component of the magnetic field in the predetermined direction according to the outcome of the projective measurements (S4).

One example includes a tunable current-mirror qubit. The qubit includes a plurality of flux tunable elements disposed in a circuit loop. A first portion of the flux tunable elements can be configured to receive a first input flux and a remaining portion of the flux tunable elements can be configured to receive a second input flux to control a mode of the tunable current-mirror qubit between a microwave excitation mode to facilitate excitation or quantum state manipulation of the tunable current-mirror qubit via a microwave input signal and a noise-protected mode to facilitate storage of the quantum state of the tunable current-mirror qubit. The qubit also includes at least one capacitor interconnecting nodes between respective pairs of the flux tunable elements to facilitate formation of Cooper-pair excitons in each of the microwave excitation mode and the noise-protected mode.

To provide a radiation analyzer that can perform analyses by a long-term stable and high energy resolution without correcting a current flowing through a transition edge sensor (hereinafter referred to as TES) or a pulse height value of a signal pulse. The radiation analyzer includes: a TES 1 configured to detect radiation; a current detection mechanism 4 configured to detect a current flowing through the TES 1; a pulse height analyzer 5 configured to measure a pulse height value based on the current detected by the current detection mechanism 4; a baseline monitor mechanism 6 configured to detect a baseline current flowing through the TES 1; a first heater 13 whose output is adjusted to stabilize a temperature of a first thermometer 12 disposed in a cold head that cools the TES 1; and a second heater 14 that is disposed fairly close to the TES 1 and whose output is adjusted to stabilize a baseline current.

A reversible memory element is provided. The reversible memory element comprises a reversible memory cell comprising a Josephson junction and a passive inductor. A ballistic interconnect is connected to the reversible memory cell by a bidirectional input/output port. A polarized input fluxon propagating along the ballistic interconnect exchanges polarity with a stationary stored fluxon in the reversible memory cell in response to the input fluxon reflecting off the reversible memory cell.

A magnetic field measurement system can include at least one magnetometer; and a ferrofluid shield disposed at least partially around the at least one magnetometer. For example, the ferrofluid shield can include a microfluid fabric and a ferrofluid disposed in or flowable into the microfluid fabric. As another example, the ferrofluid shield can include a ferrofluid and a controller configured to alter an arrangement of the ferrofluid within the ferrofluid shield.

A High Temperature Superconducting (HTS) Superconducting Quantum Interference Device and methods for fabrication can include at least one bi-Superconducting Quantum Interference Device. The bi-SQUID can include an HTS substrate that can be formed with a step edge. A superconducting loop of YBCO can be deposited on the step edge to establish two Josephson Junctions. A superconducting path that bi-sects the superconducting loop path can also be deposited onto the substrate. In some embodiments, the bisecting path can cross the step edge twice, and the bisecting path can be ion milled at one of the crossing points to round the bisecting path and thereby remove the fourth Josephson Junction at the other crossing point. In still other embodiments, the bisecting path can be completely on the upper shelf (or the lower shelf), and the bisecting path can be ion damaged, ion damaged, or particle damaged, to establish the third Josephson Junction.

A High Temperature Superconducting (HTS) Superconducting Quantum Interference Device and methods for fabrication can include at least one bi-Superconducting Quantum Interference Device. The bi-SQUID can include an HTS substrate that can be formed with a step edge. A superconducting loop of YBCO can be deposited on the step edge to establish two Josephson Junctions. A superconducting path that bi-sects the superconducting loop path can also be deposited onto the substrate. In some embodiments, the bisecting path can cross the step edge twice, and the bisecting path can be ion milled at one of the crossing points to round the bisecting path and thereby remove the fourth Josephson Junction at the other crossing point. In still other embodiments, the bisecting path can be completely on the upper shelf (or the lower shelf), and the bisecting path can be ion damaged, ion damaged, or particle damaged, to establish the third Josephson Junction.